Bottles and jars come in various shapes and sizes. Most often they come paired with caps to keep the contents from spilling out. Many bottles and jars have labels that adhere to the surface in order that the user can identify the contents. However, some bottles or jars do not have labels. Even if they do have labels, bottles and jars do not have a means for providing identification of the user. Such identification becomes necessary, for example, at a childrens' sporting event. The children drink water from their own bottles, and then put them down while playing. When they come back to take another drink, their bottles may be interspersed among water bottles belonging to other children. Due to a limited number of brands, some or all of the children could have bottles that look alike. It is undesirable to have children drinking from open bottles belonging to other children. Another example where identification marking is desirable is on prescription bottles. Bottles containing prescription drugs normally have labels identifying the drug, but a user might want to jot down the next time he or she needs a dose. It would be desirable to have a means by which a person can easily mark his or her container (e.g., jar or bottle) with identifying information. Furthermore, such means for marking should not require the use of a pen or pencil. Marking should occur merely by pressing one's fingernail on the marking section.
A number of methods exist for marking bottles and jars. Most of these require the use of a pencil and pen to transfer graphite or ink onto a writable surface. However, there are surfaces that do not require a pencil or pen to make a visible marking.                magic slate;        ink meant to fail;        lottery type rub-off material; and        microencapsulated ink.        
The magic slate is well established prior art. Since the early twentieth century, it was used by children and others to write messages and then quickly erase them. A magic slate comprises at least two components—a rigid waxy opaque surface and a thin flexible translucent material. Pressure, usually from a plastic stylus is applied to the translucent material in order to press it against the opaque surface. The pressure is applied by using the stylus to write a message. Wherever the translucent material comes in contact with the opaque surface, it loosely adheres to the opaque surface, and the color of the opaque surface is visible through the translucent material. To erase the message, the user merely pulls the translucent material away from the opaque surface. Most magic slates use a third component, i.e., a thin flexible transparent material. The translucent material is positioned between the transparent material and the opaque surface. The function of the transparent material is to protect the translucent material to prevent it from tearing because of the pressure applied to it by the stylus. Magic slates have been used to mark various packages (see U.S. Pat. No. 5,098,502 issued to Smolinski on Mar. 24, 1992).
The ink meant to fail and lottery-type rub-off surfaces are similar to each other in that material must be removed to produce an image. In both cases, a top layer of removable material is deposited on a more permanent surface. Application of pressure (e.g., from a stylus or fingernail) will remove the top layer thus exposing the more permanent surface. The ink meant to fail requires that a release agent layer (e.g., a surfactant) be applied onto the substrate below the ink layer. This agent causes the ink to bond very poorly to the substrate, thereby enabling it to be easily removed.
Finally, bank deposit slips and US Postal Service Express Mail mailing labels use microencapsulated ink to produce in image on duplicate slips and labels. This eliminates the more traditional carbon paper previously used to produce duplicates. The deposit slips and mailing labels are produced with the original and duplicates loosely fastened to each other to form a unitary product. The reverse side of the original deposit slip (as well as the reverse side of the original and one duplicate mailing label) is coated with a layer comprising microencapsulated ink. When encapsulated, the ink is invisible. Application of pressure to the original using a stylus, a fingernail, or other sharp pointed object breaks through the micro encapsulation, thereby releasing the ink and forming an image on the duplicates. If the microencapsulated ink were to be applied to the front surface rather than the rear surface of the paper, then applied pressure would produce an image directly on the front surface.